A hearing aid may be used by one who is hard of hearing and so on. Particularly, in the interest of one who is hard of hearing, the hearing aid uses on account of a supplement of the power of hearing by spreading of the power of sound from external world.
The hearing aid comprising a microphone which may be received sound from external world, a speaker which the sound may be transmitted into an ear, a body portion having an electric device (include an electric battery) which may be drove the microphone and the speaker, and the ear mold which may be inserted into a ear (the external auditory meatus) and may be joined said body portion. Said hearing aid can be amplified the sound from the outside, and this amplified sound transmits to the eardrum through said ear mold.
Said hearing aid is generally two types (kinds).
One type of the hearing aid is an ear hole type hearing aid. This ear hole type hearing aid use that an ear plug with an internal a body portion of the hearing aid inserts directly into a ear (the external auditory meatus).
The other type of the hearing aid is an ear hook type hearing aid. This ear hook type hearing aid comprises that the pipe etc. connects with the body portion of said hearing aid. This ear hook type hearing aid use that this pipe etc. hangs and supports behind an ear pinna. This ear hook type hearing aid use that the ear mold linked this pipe etc. inserts into the external auditory meatus.
Whatever an efficiency of the body portion of the hearing aid may be raised, when the ear mold cannot be adapted to a user, it gives an unpleasant feeling against the user in a long-time use, and it cannot maintain a tone's proper quality. In the ear mold for the hearing aid, the problem of occurring of a sound pee-pee and sound leak-out (what is called a phenomenon of a howling) is important thing.
However, it is difficult to adapt for user an ear plug, because external auditory meatus of the user of the ear plug is bendy and has vary between individuals.
In regard to the ear mold for the hearing aid, lately, the ear mold of a custom-made which is produced according to the order of a shape of the ear of an each user has been recommended as above-mentioned ear mold. However, said ear mold of custom-made too causes some problems that give an incompatibility feeling against the user, easily gets out of the user's ear, and occurs the phenomenon of the howling.
The forming material of the ear mold has been used a MMA (methylmethacrylate) resin, for example, but lately a silicon resin has been used as the forming material of the ear mold. Because, the silicon resin can be reduced a burden at the time of touch with the external auditory meatus, the silicon resin has not an allergy reaction and the like, consequently, the silicon resin can be adapted for the above-mentioned use.
For manufacture of the ear mold of the custom-made, generally, a forming material of an impression such as the silicon system material inserts into the external auditory meatus of the user, after hardening, the ear impression can be obtained by means of molding (forming). After spread wax and the like in a surface of said ear impression, a plaster pours into a pattern of said ear impression, and then said ear impression takes up from said pattern. After removing of said wax and a paraffin wax from said ear impression, and then a pattern of plaster make forming based on this ear impression. The forming material of the ear mold such as the silicon resin pours into said pattern of plaster, after hardening (molding) of said forming material of the ear mold, and then the ear mold of the custom-made can be obtained.
(Japan Unexamined Patent Publication No. 2000-139999).
Heretofore, as said silicon ear mold, it was proposed that said silicon ear mold shown in FIG. 18 which is prepared by the above-mentioned method and based on the ear impression picked from the user. This silicon ear mold can be made by as follows.
A tube 1802 passes into a lead-sound-hole of the silicon ear mold 1801, this tube 1802 passes through said ear mold 1801 as shown in FIG. 18, the metal bush 1803 as shown in FIG. 18 fits into an end section of this tube 1802, this tube 1802 pulls back for reasons of this metal bush 1803 puts in an end section of this silicon ear mold 1801. In this case, said metal bush 1803 has been used on account of settlement of the above-mentioned tube 1802.
However, said silicon ear mold has disadvantage that said tube 1802 is easily moved for the reason of instability, because said tube 1802 is settled by said metal bush 1803.
Also, said silicon ear mold has disadvantage that the tube 802 is destroyed by stress concentrated on the above-mentioned put-spot of ear mold 1801 when takes away by oneself, and the tube 1802 drops out from the ear mold 1801.
On the other hand, there are provided the silicon ear mold 1701 as shown in FIG. 17 which manufactured by previously-mentioned method. In this silicon ear mold 1701, a plastics-elbow or nylon-L-tube 1702 insert into the lead-sound-hole of silicon ear mold 1701 as shown in FIG. 17. Said plastics-elbow or nylon-L-tube 1702 is connected with said silicon ear mold 1701 by an adhesive. Namely, said plastics-elbow or nylon-L-tube 1702 is fixed by the glued-part 1703 of said plastics-elbow or nylon-L-tube 1702 in the inside of said silicon ear mold 1701. In said silicon ear mold 1701, as shown in the drawings, the one end portion of plastics-elbow or nylon-L-tube 1702 is connected by an adhesive in form of putting away the inside of said silicon ear mold 1701.
As shown in the drawings, the other end portion of the tube for joint of the hearing aid (vinyl tube) 1704 may be joined with said plastics-elbow or nylon-L-tube 1702.
In said silicon ear mold, the plastics-elbow or nylon-L-tube 1702 doesn't put away still the inside of said silicon ear mold 1701. Said plastics-elbow or nylon-L-tube 1702 cuts off under suitable length.
Therefore, said plastics-elbow or nylon-L-tube 1702 can be corresponded flexibility still in case of small of the external auditory meatus. Said plastics-elbow or nylon-L-tube 1702 is different from said silicon ear mold 1801 as previously mentioned as shown in FIG. 18.
For reason of stiffen of said vinyl tube 1704 became increase with use, it is necessary to change periodically, but said vinyl tube 1704 is not one-body and is independent from said ear mold 1701 through the intervention of said plastics-elbow or nylon-L-tube 1702, therefore the working of exchange become easy.
But, said silicon ear mold has problems that intensity of adhesive become lack, said plastics-elbow or nylon-L-tube 1702 detaches easily or drops out from said ear mold 1701, and occurs the phenomenon of the howling by a sound pee-pee and sound leak-out.
On the other hand, the present inventor was provided newly the silicon ear mold used a hub as shown Figure from 14 to 16 which can be dissolved the problems issued at those prior art technologies (International Publication Number WO/2006/082735).
In the silicon ear mold, as shown FIGS. 14 and 15, a hub 1402 such as shown FIG. 16 is embedded in an ear mold 1401, this hub 1402 has the function of relaying, this hub 1402 can be transmitted the sound from the era hook hearing aid to the eardrum.
A body portion 1402A of the hub 1402 has two introductory holes 1402A1 and 1402A2 of the forming material of the ear mold, the hub 1402 may be contacted and fixed with the forming material of the ear mold 1401 through said two introductory holes 1402A1 and 1402A2.
An elbow 1403 joins with the joint-hole 1402B0 of a joint portion 1402B of the hub 1402, this elbow 1403 joins with a tube for joint of the hearing aid 1404.
The silicon ear mold has a sound-guiding hole 1405 formed by molding material of the silicon ear mold.
In said silicon ear mold, the sound of the era hook hearing aid can be transmitted to the eardrum by relaying of said hub 1402 after through a sound-guiding hole 1405 formed by hole-opening.
According to the silicon ear mold, it can be supported a relation ship of a position between the hearing aid and the ear mold and can be increased the improvement of stability of using when the ear mold puts into the hearing aid, because the hub 1402 was embedded in the ear mold and the hub 1402 was connected and fixed with the forming material of the ear mold at the introductory-hole for the forming material of the ear mold (the hole in order to fix with mold) 1402A1 and 1402A2.
However, when, the side of the external auditory meatus joins with a sound-leading tube as substitute for the above-mentioned sound-guiding hole 1405 formed by molding material of the silicon ear mold, it has the problems that said sound-leading tube become flabby accordingly climb-down and become bend easily at a right angle, it can't act as a kind of said sound-leading tube by reason of impassableness of the sound, and the bend of thereof make by specially proper angle fitted for the people become restores, when heating.
Furthermore, in case of joint which the sound-leading tube with the hub, it is necessary that said sound-leading tube joints with accordingly under adjustment of desired-angle of bend, because the external auditory meatus of the user is bendy-bendy and has vary personal difference, nevertheless it has the problems that the sound-leading tube can not put forward till deeply in the mold, in the case of contact with the inner-wall surface of the mold, search for ways to circumvent, it can not be clinched as avoid with the inner-wall surface of the mold.
[Patent Document 1] Japan Unexamined Patent Publication No. 2000-139999